Expected impacts of climate change threaten the anuran diversity in the Brazilian hotspots

Abstract

We performed Ecological Niche Models (ENMs) to generate climatically suitableareas for anurans in the Brazilian hotspots, the Atlantic Forest (AF), and Cerrado(CER), considering the baseline and future climate change scenarios, to evaluate thedifferences in the alpha and beta diversity metrics across time. We surveyed anuranoccurrence records and generated ENMs for 350 and 155 species in the AF and CER.The final predictive maps for the baseline, 2050, and 2070 climate scenarios, basedon an ensemble approach, were used to estimate the alpha (local species richness)and beta diversity metrics (local contribution to beta diversity index and its decomposition into replacement and nestedness components) in each ∼50 × 50 km grid cellof the hotspots. Climate change is not expected to drastically change the distributionof the anuran richness gradients, but to negatively impact their whole extensions(i.e., cause species losses throughout the hotspots), except the northeastern CERthat is expected to gain in species richness. Areas having high beta diversity are expected to decrease in northeastern CER, whereas an increase is expected in southeastern/southwestern CER under climate change. High beta diversity areas areexpected to remain in the same AF locations as the prediction of the baseline climate,but the predominance of species loss under climate change is expected to increasethe nestedness component in the hotspot. These results suggest that the lack ofsimilar climatically suitable areas for most species will be the main challenge that species will face in the future. Finally, the application of the present framework to a widerange of taxa is an important step for the conservation of threatened biomes.